Ambient temperature and the occurrence of collective violence: A new analysis.

Journal of Personality and Social Psychology, 37, 337-344.

Abstract

Prevalent folklore suggests that riots tend to occur during periods of
very hot weather. Baron and Ransberger examined 102 major riots in the United
States between 1967 and 1971 and concluded that the frequency of collective
violence and ambient temperature are curvilinearly related. The present article
points out that the Baron and Ransberger analysis did not take account of
the different number of days in different temperature ranges. The artifact
is eliminated, and the probability of a riot, conditional upon temperature,
is estimated. When this is done, the evidence strongly suggests that the
conditional probability of a riot increases monotonically with temperature.
Some general implications of such data analyses are discussed.